The present invention relates generally to interconnection closures and, more particularly, to interconnection closures including a fiber management frame having a movable work platform for supporting and securely retaining various sized optical fiber connection trays and test equipment adjacent the fiber management frame.
Fiber optic networks typically include interconnection closures at splice locations throughout the fiber optic network. Typically, these interconnection closures include splice closures, patch closures and the like. For example, splice closures commonly house the splices required to connect the optical fibers of one or more fiber optic feeder cables to respective ones of the optical fibers of one or more fiber optic drop cables. By housing the splices, a splice closure protects the spliced end portions of the optical fibers from strain, environmental degradation, and other deleterious forces, thereby increasing the reliability and quality of the splices.
While fiber optic networks have traditionally served as the backbone or trunkline of communication networks to transmit signals over relatively long distances, fiber optic networks are gradually being extended closer to the end points of the communications networks. In this regard, fiber optic networks have been developed that deliver fiber-to-the-curb, fiber-to-the-home, fiber-to-the-business, fiber-to-the-desk, and the like. In each of these different applications, a splice closure must be capable of splicing different types of cables to establish the proper interconnections. In this regard, the splice closure utilized in a fiber-to-the-home, fiber-to-the-business, or fiber-to-the-desk application is mounted upon a fiber optic feeder cable and one or more fiber optic drop cables to permit at least some of the optical fibers of the feeder cable to extend uninterrupted through the splice closure while splicing or otherwise connecting the other optical fibers of the fiber optic feeder cable with optical fibers of the drop cable(s). In contrast, a splice closure that is utilized in a fiber-to-the-curb application is mounted upon not just a fiber optic feeder cable and one or more drop cables, but also an electrical feeder cable. In this application, the splice closure must facilitate the splicing of one or more electrical conductors of the electrical feeder cable to corresponding electrical conductors of the drop cable(s), while permitting the remainder of the electrical conductors to extend uninterrupted through the closure. Additionally, the splice closure must facilitate the splicing of one or more of the optical fibers of the fiber optic feeder cable with respective optical fibers of the drop cable(s) while continuing to permit at least some of the optical fibers of the fiber optic feeder cable to extend uninterrupted through the closure.
In either type of splice closure, the closure must provide a mechanism for connecting optical fibers, such as splicing one or more optical fibers of a fiber optic feeder cable with respective optical fibers of a drop cable, and for testing the continuity of the optical fiber connections, both during initial configuration and subsequent reconfiguration of the splice closure. Typically, the splice closure includes one or more splice trays, coupler trays and/or connector panels that facilitate the splicing or other connection of respective pairs of the optical fibers. For ease of reference, splice trays, coupler trays, and connector panels will be hereinafter collectively referred to as xe2x80x9coptical fiber connection traysxe2x80x9d or simply xe2x80x9ctrays.xe2x80x9d Each such tray is designed to house a plurality of connections between respective pairs of optical fibers. Since many splice closures include a large number of connections between respective pairs of optical fibers, splice closures oftentimes include a plurality of trays, typically stacked one upon another and/or stored in separate compartments within the splice closure.
The trays are preferably secured within the splice closure such that they are fixed in position once the closure has been configured and is placed into service. As such, the trays should not shift or otherwise move once the splice closure has been placed into service since any shifting or other movement of the trays could harm the connections between respective pairs of optical fibers. Some splice closures include a strap, such as a hook and loop strap, that wraps about the trays to secure the trays in position. Alternatively, the trays may define an aperture and the splice closure may include a post upon which the trays are mounted such that the post extends through the corresponding apertures defined by the trays, thereby securing the trays in position. Other means for securing the trays within the closure are described in the co-pending U.S. Patent Application entitled Fiber Management Frame For Securely Retaining Optical Fiber Connection Trays filed by Jennifer Battey, et al. and assigned to the assignee of the present application, the disclosure of which is hereby incorporated by reference in its entirety.
While the trays are desirably fixed in position once the splice closure has been configured and placed in service, the closure is also preferably designed such that the trays can be readily accessed by a technician both during the initial configuration of the closure in which connections are established between respective pairs of the optical fibers and during any subsequent reconfiguration of the closure in which at least some of the connections between respective pairs of the optical fibers are changed. For splice closures that include a strap for retaining stacked trays, the strap must be released and the appropriate tray removed from the stack. For splice closures that include a plurality of stacked trays mounted upon an upstanding post, the appropriate tray must be removed from the post and the stack. In either instance, the tray must then be supported and securely retained in a convenient work location where it can be opened to provide the technician with access to the optical fiber connections housed by the tray.
Reconfiguring an aerial splice closure is especially difficult, particularly in applications, such as previously discussed, when at least some of the optical fibers of the optical fiber feeder cable and/or at least some of the electrical conductors of the electrical feeder cable extend uninterrupted through the closure. In such applications, sometimes referred to as xe2x80x9ctaut sheathxe2x80x9d applications, the splice closure cannot be removed from the fiber optic feeder cable, the electrical feeder cable, and the drop cables. Accordingly, the aerial splice closure must be reconfigured from a ladder or an aerial bucket of a utility truck that is positioned in close proximity to the closure. It is known to provide a work platform on the ladder or the aerial bucket. However, the work platform provided on the ladder or aerial bucket cannot always be positioned sufficiently close to the fiber management frame of the splice closure, for example when the cover of the closure interferes with the ladder or aerial bucket in its open position. Furthermore, work platforms provided on ladders and aerial buckets typically are not adapted for securely retaining the various sized trays housed within different splice closures or the various sized test equipment utilized, for example, to verify the continuity of the optical connections.
Not only does positioning various sized trays and test equipment on the work platform of a ladder or aerial bucket create additional work for the technician reconfiguring the splice closure, but the additional movement of the trays increases the risk that the optical fiber connections housed by the trays will be damaged during the reconfiguration. As such, it would be desirable to provide a splice closure with a movable work platform for supporting any one of the trays without having to remove the tray from the closure and to support the tray on a work platform provided on a ladder or an aerial bucket. More particularly, it would be desirable to develop a splice closure including a fiber management frame having a movable work platform for supporting and securely retaining various sized trays and test equipment adjacent the fiber management frame during initial configuration and reconfiguration of the closure. Furthermore, it would be desirable to develop a splice closure having a movable work platform that permits a technician to more readily support and retain any one of the optical fiber connection trays without damaging the optical connections housed by the tray.
A fiber management frame having a movable work platform and an interconnection closure including the fiber management frame are provided for supporting and securely retaining various sized optical fiber connection trays and test equipment adjacent the fiber management frame during initial configuration and reconfiguration, while also permitting a technician to readily support and retain any one of the trays without damaging the optical connections housed by the tray.
According to one aspect of the present invention, an interconnection closure includes a fiber management frame and a work platform movably attached to the fiber management frame. The work platform includes means for supporting and securely retaining various sized optical fiber connection trays selected from the consisting of a splice tray, a coupler tray, and a connector panel. The means for supporting and securely retaining includes a shelf having an inner edge adjacent the fiber management frame and an outer edge opposite the inner edge, a bias member positioned on the shelf, and at least one first outer flange extending upwardly from the shelf and positioned opposite the bias member. The bias member engages a lengthwise edge of the trays and biases the tray in the direction of the first outer flange to securely retain the tray between the bias member and the first outer flange. The means for supporting and securely retaining further includes at least one first inner flange extending upwardly from the shelf adjacent the inner edge of the shelf. The first inner flange has an aperture therethrough for receiving a fastener for affixing the work platform to the fiber management frame. The means for supporting and securely retaining further includes at least one second inner flange extending upwardly from the shelf and the bias member is affixed to the second inner flange.
In another aspect of the present invention, the work platform is hingedly mounted to the fiber management frame and the means for supporting and securely retaining includes a hinge. The hinge has a first half affixed to the fiber management frame and a second half affixed to the work platform. More particularly, the second half of the hinge is affixed to the underside of the inner edge of the shelf adjacent the fiber management frame. As previously described, the means for supporting and securely retaining further includes a first inner flange extending upwardly from the shelf adjacent the inner edge. The first inner flange has an aperture therethrough for receiving a fastener for affixing the work platform to the fiber management frame in an operational position. The means for supporting and securely retaining further includes a second outer flange extending outwardly from the shelf. The second outer flange has an aperture therethrough for receiving a fastener for affixing the work platform to the fiber management frame in a stowed position.
In another aspect of the present invention, a fiber management frame having a movable work platform adjacent the fiber management frame is provided for supporting and securely retaining various sized optical fiber connection trays. The work platform includes a shelf having an inner edge adjacent the fiber management frame and an outer edge opposite the inner edge. The work platform further includes a bias member positioned on the shelf and a first outer flange extending upwardly from the shelf and opposite the bias member. The bias member engages a lengthwise edge of the trays and bias the tray in the direction of the first outer flange. The work platform further includes at least one first inner flange extending upwardly from the shelf adjacent the inner edge of the shelf. The first inner flange has an aperture therethrough for receiving a fastener for affixing the work platform to the fiber management frame. The work platform further includes at least one second inner flange extending upwardly from the shelf and the bias member is affixed to the second inner flange.
In another aspect of the present invention, the bias member of the work platform is a thin, elongate strip of elastic material having a first end affixed to the second inner flange, a second end opposite the first end and positioned adjacent and parallel to the second inner flange, and an outermost portion opposite the first outer flange. The outermost portion engages a lengthwise edge of the trays and biases the tray in the direction of the first outer flange. The bias member thereby exerts pressure on the lengthwise edge of the trays to securely retain the tray between the outermost portion of the bias member and the first outer flange. In a preferred embodiment, the bias member is formed of spring steel, the first end of the bias member is affixed to the second inner flange, and the second end of the bias member is free to slide parallel to the second inner flange beneath a guide flange. As previously described, the first inner flange extends upwardly from the shelf adjacent the inner edge of the shelf and has an aperture therethrough for receiving a fastener for affixing the work platform to the fiber management frame in an operational position. The second outer flange extends outwardly from the shelf and has an aperture therethrough for receiving a fastener for affixing the work platform to the fiber management frame in a stowed position. The work platform may further include a hinge having a first half affixed to the fiber management frame and a second half affixed to the shelf such that the shelf rotates about the hinge between the operational position and the stowed position.
In yet another aspect of the present invention, a method is provided for supporting and securely retaining various sized optical fiber connection trays on a movable work platform adjacent a fiber management frame housed within an interconnection closure. The work platform includes a shelf, a bias member positioned on the shelf, and a first outer flange extending upwardly from the shelf and positioned opposite the bias member. The method includes the first step of positioning the work platform in an operational position adjacent the fiber management frame. The method further includes the second step of removing one of the trays from the fiber management frame. The method further includes the third step of positioning the tray on the work platform between the bias member and the first outer flange such that the bias member biases the tray in the direction of the first outer flange. Preferably, the work platform further includes a first inner flange extending upwardly from the shelf adjacent the inner edge that has an aperture therethrough for receiving a fastener for affixing the work platform to the fiber management frame in an operational position, and a second outer flange extending outwardly from the shelf that has an aperture therethrough for receiving a fastener for affixing the work platform to the fiber management frame in a stowed position. As previously mentioned, the work platform is hingedly mounted to the fiber management frame and the work platform includes a hinge such that the shelf rotates about the hinge between the operational position and the stowed position.